Detailed Description

An interface for recording/playback animations in Meshcat.

Use Meshcat::SetAnimation to publish a MeshcatAnimation to the visualizer.

Currently, an animation consists of (only) transforms and properties that are set at a particular integer frame number. Although we do not support calls to SetObject/Delete in an animation, you can consider using SetProperty(frame, path, "visible", true/false) in your animation to make the object appear or disappear at a particular frame.

#include <drake/geometry/meshcat_animation.h>

Public Types
enum	LoopMode { kLoopOnce = 2200, kLoopRepeat = 2201, kLoopPingPong = 2202 }

Public Member Functions
	MeshcatAnimation (double frames_per_second=64.0)
	Constructs the animation object. More...

	~MeshcatAnimation ()

double	frames_per_second () const
	Returns the frame rate at which the animation will be played back. More...

int	frame (double time) const
	Uses the frame rate to convert from time to the frame number, using std::floor. More...

double	start_time () const

bool	autoplay () const

LoopMode	loop_mode () const

int	repetitions () const

bool	clamp_when_finished () const

void	set_start_time (double time)
	Set the start time of the animation. More...

void	set_autoplay (bool play)
	Set the behavior when the animation is first sent to the visualizer. More...

void	set_loop_mode (LoopMode mode)
	Sets the loop behavior on play. More...

void	set_repetitions (int repetitions)
	Sets the number of repetitions of the animation each time it is played. More...

void	set_clamp_when_finished (bool clamp)
	Sets the behavior at the end of the animation. More...

void	SetTransform (int frame, std::string_view path, const math::RigidTransformd &X_ParentPath)
	Set the RigidTransform at `frame` in the animation for a given `path` in the the scene tree. More...

void	SetProperty (int frame, std::string_view path, std::string_view property, bool value)
	Sets a single named property of the object at the given `path` at the specified `frame` in the animation. More...

void	SetProperty (int frame, std::string_view path, std::string_view property, double value)
	Sets a single named property of the object at the given `path` at the specified `frame` in the animation. More...

void	SetProperty (int frame, std::string_view path, std::string_view property, const std::vector< double > &value)
	Sets a single named property of the object at the given `path` at the specified `frame` in the animation. More...

template<typename T >
std::optional< T >	get_key_frame (int frame, std::string_view path, std::string_view property) const
	Returns the value information for a particular path/property at a particular frame if a value of type T has been set, otherwise returns std::nullopt. More...

std::string	get_javascript_type (std::string_view path, std::string_view property) const
	Returns the javascript type for a particular path/property, or the empty string if nothing has been set. More...

Does not allow copy, move, or assignment
	MeshcatAnimation (const MeshcatAnimation &)=delete

MeshcatAnimation &	operator= (const MeshcatAnimation &)=delete

	MeshcatAnimation (MeshcatAnimation &&)=delete

MeshcatAnimation &	operator= (MeshcatAnimation &&)=delete

Friends
class	Meshcat

Member Enumeration Documentation

◆ LoopMode

enum LoopMode

Enumerator
kLoopOnce	Plays the clip once.
kLoopRepeat	Plays the clip with the chosen number of repetitions, each time jumping from the end of the clip directly to its beginning.
kLoopPingPong	Plays the clip with the chosen number of repetitions, alternately playing forward and backward.

Constructor & Destructor Documentation

◆ MeshcatAnimation() [1/3]

MeshcatAnimation ( const MeshcatAnimation & )

delete

◆ MeshcatAnimation() [2/3]

MeshcatAnimation ( MeshcatAnimation && )

delete

◆ MeshcatAnimation() [3/3]

MeshcatAnimation ( double frames_per_second = 64.0 )

explicit

Constructs the animation object.

Parameters

frames_per_second a positive integer specifying the timing at which the frames are played back.

◆ ~MeshcatAnimation()

~MeshcatAnimation ( )

Member Function Documentation

◆ autoplay()

bool autoplay ( ) const

◆ clamp_when_finished()

bool clamp_when_finished ( ) const

◆ frame()

int frame ( double time ) const

Uses the frame rate to convert from time to the frame number, using std::floor.

Precondition: time ≥ start_time().

◆ frames_per_second()

double frames_per_second ( ) const

Returns the frame rate at which the animation will be played back.

◆ get_javascript_type()

std::string get_javascript_type	(	std::string_view	path,
		std::string_view	property
	)		const

Returns the javascript type for a particular path/property, or the empty string if nothing has been set.

This method is intended primarily for testing.

◆ get_key_frame()

std::optional<T> get_key_frame	(	int	frame,
		std::string_view	path,
		std::string_view	property
	)		const

Returns the value information for a particular path/property at a particular frame if a value of type T has been set, otherwise returns std::nullopt.

This method is intended primarily for testing.

Template Parameters

T	One of `bool`, `double`, or `vector<double>`

◆ loop_mode()

LoopMode loop_mode ( ) const

◆ operator=() [1/2]

MeshcatAnimation& operator= ( MeshcatAnimation && )

delete

◆ operator=() [2/2]

MeshcatAnimation& operator= ( const MeshcatAnimation & )

delete

◆ repetitions()

int repetitions ( ) const

◆ set_autoplay()

void set_autoplay ( bool play )

Set the behavior when the animation is first sent to the visualizer.

The animation will play immediately iff play is true. The default is true.

◆ set_clamp_when_finished()

void set_clamp_when_finished ( bool clamp )

Sets the behavior at the end of the animation.

If true, then the animation will automatically be paused on its last frame. If false, the scene will be reset to before the animation. The default is true.

Note: This setting has no impact if the action is interrupted (it has only an effect if its last loop has really finished).

◆ set_loop_mode()

void set_loop_mode ( LoopMode mode )

Sets the loop behavior on play.

See also: LoopMode for details. The default is kLoopRepeat.

◆ set_repetitions()

void set_repetitions ( int repetitions )

Sets the number of repetitions of the animation each time it is played.

This number has no effect when the loop mode is set to kLoopOnce. repetitions must be a positive integer. The default value is 1.

◆ set_start_time()

void set_start_time ( double time )

Set the start time of the animation.

This is only for convenience; it is used in the frame() method to allow callers to look up the frame number based on the current time, the start time, and the frame rate. It is not passed to Meshcat. It does not change any frames that have previously been set. The default is zero.

◆ SetProperty() [1/3]

void SetProperty	(	int	frame,
		std::string_view	path,
		std::string_view	property,
		bool	value
	)

Sets a single named property of the object at the given path at the specified frame in the animation.

See also: Meshcat::SetProperty.

Parameters

frame	a non-negative integer indicating the frame at which this transform is applied.
path	a "/"-delimited string indicating the path in the scene tree. See Meshcat paths and the scene tree for the semantics.
property	the string name of the property to set
value	the new value.

Exceptions

std::exception if this path/property has already been set with a different type.

◆ SetProperty() [2/3]

void SetProperty	(	int	frame,
		std::string_view	path,
		std::string_view	property,
		double	value
	)

Sets a single named property of the object at the given path at the specified frame in the animation.

See also: Meshcat::SetProperty.

Parameters

frame	a non-negative integer indicating the frame at which this transform is applied.
path	a "/"-delimited string indicating the path in the scene tree. See Meshcat paths and the scene tree for the semantics.
property	the string name of the property to set
value	the new value.

Exceptions

std::exception if this path/property has already been set with a different type.

◆ SetProperty() [3/3]

void SetProperty	(	int	frame,
		std::string_view	path,
		std::string_view	property,
		const std::vector< double > &	value
	)

Sets a single named property of the object at the given path at the specified frame in the animation.

See also: Meshcat::SetProperty.

Parameters

frame	a non-negative integer indicating the frame at which this transform is applied.
path	a "/"-delimited string indicating the path in the scene tree. See Meshcat paths and the scene tree for the semantics.
property	the string name of the property to set
value	the new value.

Exceptions

std::exception if this path/property has already been set with a different type.

◆ SetTransform()

void SetTransform	(	int	frame,
		std::string_view	path,
		const math::RigidTransformd &	X_ParentPath
	)

Set the RigidTransform at frame in the animation for a given path in the the scene tree.

See also: Meshcat::SetTransform.

Parameters

frame	a non-negative integer indicating the frame at which this transform is applied.
path	a "/"-delimited string indicating the path in the scene tree. See Meshcat paths for the semantics.
X_ParentPath	the relative transform from the path to its immediate parent.

Exceptions

std::exception if the position or quaternion properties of this path have already been set to an incorrect type.

◆ start_time()

double start_time ( ) const

Friends And Related Function Documentation

◆ Meshcat

friend class Meshcat

friend

The documentation for this class was generated from the following file:

drake/geometry/meshcat_animation.h

Detailed Description

Public Types

Public Member Functions

Friends

Member Enumeration Documentation

◆ LoopMode

Constructor & Destructor Documentation

◆ MeshcatAnimation() [1/3]

◆ MeshcatAnimation() [2/3]

◆ MeshcatAnimation() [3/3]

◆ ~MeshcatAnimation()

Member Function Documentation

◆ autoplay()

◆ clamp_when_finished()

◆ frame()

◆ frames_per_second()

◆ get_javascript_type()

◆ get_key_frame()

◆ loop_mode()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ repetitions()

◆ set_autoplay()

◆ set_clamp_when_finished()

◆ set_loop_mode()

◆ set_repetitions()

◆ set_start_time()

◆ SetProperty() [1/3]

◆ SetProperty() [2/3]

◆ SetProperty() [3/3]

◆ SetTransform()

◆ start_time()

Friends And Related Function Documentation

◆ Meshcat